Under-roofs produced in profiled materials are known, particularly corrugated materials that also have, in certain cases, alternating corrugations and flat areas. FR Patent 2 496 551 describes materials of this type.
Such a profiled material can also be used to produce light weight roofs.
Furthermore, corrugated under-roof materials are more particularly intended for arched tiles. They have good qualities since they make the roof leak-tight, even if a tile is displaced or broken, and they guarantee natural ventilation of the roof.
This is why, corrugated panels have also been used to produce under-roofs intended for roofs with flat tiles.
In order to be able to lay flat tiles, it is necessary to first fix battens onto the under-roof, the battens being used as the hanger for the tiles.
Fixing battens onto corrugated panels does however have disadvantages. In particular, the weight of the battens and the tiles is almost entirely supported by the summits of the corrugations which have a tendency to deform.
This weakens the under-roof. Moreover, the deformation of the under-roof can impair good ventilation of the roof and prevent the run-off of water that has possibly infiltrated through a damaged tile.
That is why members have been designed to support and to distribute the loads, these members being intended to be placed between the battens and the under-roof, at specified intervals.
In this regard, FR patent 2 658 848 may be mentioned which describes a support and load distribution member consisting of a tubular crosspiece arranged in a concave corrugation of the under-roof. Such a member permits good distribution of the loads and does not prevent the passage of air for the ventilation of the roof.
However, the presence of battens and support and load distribution members extends the time taken to produce roofs and has a not insignificant effect on their cost. They may also block, at least in part, the passage of air between the tiles and the under-roof, as well as the run-off of water.
It is furthermore, desirable to simplify the production of roofs with flat tiles.
It has also appeared necessary to make the profiled materials more rigid, whether they are intended for use as a roofing material or as an under-roofing material, in order to extend the life of the roof.